Vladimir Putin is learning a lesson that President Barack Obama already knows: that war has unforeseen consequences and events can spin out of control.

That was a lesson the United States learned from its misadventure in Iraq. One of Obama’s missions as president has been to put that lesson into effect, seeking to find the proper balance between prudence and aggression.

Putin’s role in provoking the uprising by separatists in eastern Ukraine is unmistakable. Details about the destruction of the Malaysian airliner, shot down over Ukraine, are still not clear, but so far all signs point to the pro-Russian separatists who have been using Russian weapons in the region where the plane was shot down.

Obama was careful at his news conference Friday to say he did not want to get ahead of the facts as they were understood at the time. But to those looking on from a distance, the facts pointed toward separatists who had their hands on Russian antiaircraft weapons and who already had shown they were willing to shoot planes out of the sky.

Early in the day, the BBC was airing recordings of what were apparently phone conversations among separatist officers who were surprised to learn that the plane they had destroyed was actually a civilian passenger liner. The authenticity of the tapes was still being examined.

There is nothing pointing to actual Russian culpability in intentionally shooting down the plane. What Russia is culpable of is fomenting rebellion within the territory of Ukraine by sending in personnel and weapons. When any nation sets a rebellion in motion, unforeseen events are bound to happen. It happened among rebels fighting Russians in Afghanistan who were supported by the United States. One of them was Osama bin Laden.

There is little reason to believe the separatists in Ukraine are paragons of virtue or competence. They had already shot down a Ukrainian cargo plane, and now they have apparently blundered toward the mistake of shooting down an airliner carrying 298 innocent people from Amsterdam to Kuala Lumpur.

The struggle is on to reach solid conclusions about the circumstances of the crash, and Putin is likely to try to thwart that effort where possible. Already, he has put himself on record saying that he believed the missile was launched by Ukraine because the crash took place on Ukrainian territory — a laughable claim given that he has done what he could to put his henchmen in charge of the territory in question.

International pressure on Russia now ought to become more severe. Europe has been attacked; most of the passengers were Dutch. Russian support of the rebels in Ukraine will increasingly be seen as a criminal enterprise. Germany and others who depend on Russian oil and gas will have to loosen Russia’s grip on their economies.

One commentator has noted that Putin has a Goebbels-like relation to the truth, referring to the Nazi minister of propaganda. Every comment by Putin appears to be a cover for an action that is exactly contrary to his expressed statement. The downing of the Malaysian airliner, as tragic as it is, may have the beneficial effect of bringing clarity to the question of Russia’s role and the insurgents’ aims.

Obama has been careful not to react with hysteria to events in Ukraine, and he refrained from bluster in his comments Friday. Actions speak for themselves, and if the airliner disaster causes Europe and the United States to tighten the screws further on Russia, then Putin may finally see that he has gone too far.

Early in the Ukraine conflict, observers said Putin had wandered into a quagmire. Now the goal ought to be to give him a path out so as to promote peace and stability in Ukraine. Putin found himself deeper in the quagmire with the downing of the Malaysian airliner, which may finally persuade him to pull back from the crisis he helped create.